Machine for mixing and placing concrete and other material.



w; e. WILSON.

MACHINE FDR MIXING AND PLACING CONCRETE AND OTHER MATERIAL.

APPLICATION FILED MAY 4,1917.

Patented Jan. 7, 1919.

LQQUAW m m Q U n UNITED STATES PATENT- OFFICE.

' LIE GEMMEL WILSON, OF ELIZABETH, NEW JERSEY, ASSIGNOR, BY'MESNE ASSIGN- MENTS, TO EVERLASTING VALVE COMPANY, A CORPORATION OF NEW JERSEY.

MACHINE FOR MIXING AND PLACING- CONCRETE AND OTHER lHLA'IEERIAIt.

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Specification Bf Letters Patent;

Application filed May a, 1917. sex-mite. mama.

To all 'wlwm itmay concern Be it own that I, WYIIE-GEMMEL WIL- I sort, a subject of the King of Great- Britain,

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residing at Elizabeth, in the county of "Union and State of New Jersey, have invented certain new and useful Improvements in Machines for Mixing and Placing Concrete and other Material, of which the following is a specification.

The main object of the invention is to efl'ect a new and increased rapidity of the discharge of mixed concrete-forming aggregates or other-material v.from a compressedair-containing chamber.

llnthe accompanying drawings forming a part hereof and illustrating the principle of my invention in the best mode now known to me of applying that principle,

Figure 1 is a vertical central sectional elevation of my new concrete mixing and placing machine, through the axis of rotation of its drum; and

Fi 2 is an end view of an adjustable shiel for covering the inward intake end of the material-discharge pipe during the mixing operation.

Referring to the drawings, the revoluble drum 1 is provided with. interior-mixing, lifting and spilling blades 2 and is rotated in a well-known way by well-known means.

The blades 2 are carried by the interior wall of the drum and in the preferred form as shownare each scoop-shaped, being of approximately triangular shape in plan view. Each end portion of a blade is inclined toward its mid-section, and its apical portion is at the front edge ofthe mid-section. As these scoop-shaped blades successively come-to the top of the drum in its rotation for discharge of the mixed material afterthe aggregates have been properly mixed by previous rotation of the drum, they severally discharge seriatz'm into the open upstanding'end of the discharge pipe 3. This upstanding end portion of the discharge pipe 3 curves downwardly to a horizontal portion of the pipe which is fixed tightly in a pair of collars 4 that are fixed 1n an annulus 5 which leads out of the drum through a central opening in its discharge end. Stufiing-box members 6 are used to form an air-tight connection of the annulus 5 in such central opening of the drum, the

collars are fixed air-tightly in the annulus around the pipe 3, and the assemblage of the collars, annulus, discharge pipe and stufiing-box members is stationary and is in part supported by a strut 7 whichis fixed at its upper end to the projecting end of the annulus 5 and fixed at its lower end by its foot 8 to the frame base.

An air inlet pipe 9, assumed to lead from an an recelver of an air-compressing apparatus, and having a control valve 10, is airtlghtly fixed in holes through thecollars 4 with its inner. discharge end openinto the drum chamber and not into the discharge pi e 3. %uring the mixing of the aggregates the open end of the discharge pipe within the drum chamber is closed against admission Patented J tum-7,1919.

into it of the mixed aflgregates by means of a'shield 11 which is fixed to the inner arm l2 of a horizontal rocker shaft 13 which is journaled in holes through collars 4 and provided at its exterior end.with a crank handle 14 by a movement of which the shield is rocked into or out of position above the f open up-turned end of the discharge pipe 3. v

The upper sides of the shield aredown wardly slanted so that materialdropped on' it by the blades during the mixing operation will not lodge thereon, but will slide off and is ournaled in an exterior projecting boss 17 of the drum end. A crank handle 18 fixed to theoutward end of the hinge pin 16 serves for opening and closing the door the margin of which makes a suitably tight joint with the margin of the intake opening of the drum and when the door is in closed position.

The scoop shape of the mixing, lifting and spilling blades is not new with me, and various changes may be made in the form of my invention without departing from it.

The glandmembers 6, 6 rotate with the drum around the stationary annulus 5 as a bearing, one of the members being fixed to and projecting from thedrum, and the other being connected therewith, as by a screw 63in a known way.

A novel and very important mode of operation is involved in the described construction. The material discharge pipe, 3 is shown of uniform diameter, its'outwardly projecting end being constructed to be coupled with a pipe or flexible placing hose :1: m the usual way. Heretofore the desirable rapidity of discharge of the mixed concrete by compressed air has not been obtainable in practice for a variety of reasons, one of which is that at the greater bend of the material discharge pipe as at y the materlal appears usually to encounter undue skin friction with the inner wall of the discharge pipe; and generally speaking, and so far as I am aware, the compressed air used for effecting the discharge has tended e1ther to wedge a conoidal mass or to force the outer walls of a mass of other shape against the inner wall of the discharge pipe, thereby hindering the requisite rapidity of discharge and very often resulting in nondischarge or an intermittent discharge of the concrete from the machine. It has been hitherto proposed to form a conoidal mass of the mixed aggregates in the discharge conduit, compactin the mass as a plug or wad by compresse -air pressure on its inward end, and then to move the wad or plug in more or less balanced pressure out ofthe discharge pipe. This mode of operatlon as above indicated results in forcing the soggy concrete mixture'against the inner wall of the pipe to a considerable extent, and involves undue skin friction. Again, it has been proposed to drive a body of the mixed material out of a concrete-containing compartment by means of an airblast which pushes a charge of the mixture out of the compartment into a discharge pipe. And again, it has been proposed to introduce a blast of compressed air into the base of a discharge hopper and so entrain a charge of the wet mass on the principle of an injector and shoot it through a discharge pipe. The lattercase often results in a bridging of the material above the compressed-air entraining current, and the air blast itself at the base portion of a hopper ofiers some resistance to the movement thereinto of the mixed aggregates. The chamber of the drum is filled with air under a eater pressure than the outside atmosphenc pressure, and this air rushes from all directions within the drum into the upper or hopper end of the upstanding portion of the discharge pipe,

- and flows as a current out through the discharge pipe and into the placing hose or conduit :12. The velocity of the escaping air current is greatest at the mouth of the upper receiving or hopper end of the discharge pipe, and as the blades successively reaching the upper portion of the drum severally spill a stream downward through the compressed-air volume in the drum bination with a bent quently, the compressed-air current instead of spreading or tending to spread and thereby force the material against the interior wall of the pipe 3, appears ver clearly to form more or less of; an air fi between theexterior of the material and the interior wall of the pipe 3, cutting down the 'skin friction and particularly eliminating the resistance which this material generally has in passin the larger bend as at y. Bridgingand c ogging in the the receiving end of the discharge plpe are prevented, and the material is by more or less intermixture with the compressedeair current conveyed, rather than caused to travel b a forcing pressure or by entrainment on e principle of an injector. The stream of material and the outflowing compressed-air current both move in the same direction each at its highest velocity, and unite in the discharge pipe as a current and with a minimum diminution of the stream and current velocities. There is no impingment of the stream on the air current at an angle thereto, or vice versa, at the moment of entry of the material into the air current. v

What I claim is 1. The combination of a drum having an inlet means for material and interior revoluble mixing, lifting and spilling blades, said drum having a bearin in one end, in combination with a bent discharge pipe which is tubular from end to end and which has within the drum chamber an upstanding tubular portion, the upper tubular end of which is open, adjacent and below the discharge end of a blade as the blade comes to the top of the drum, the discharge pipe within the drum chamber being closed. to the admission of air except at its said upper open tubular end; and a compressed air supply pipe which discharges directly into the drum chamber.

2. The combination of a drum having an inlet means for material and interior revoluble mixing, lifting and spilling blades, said drum having a bearin in one end, in comdischarge pipe which is tubular from end to end and which has within the drum chamber an upstanding tubular portion, the upper tubular end of which is open, adjacent and below the discharge end of a blade as the blade comes to the top of the drum, the discharge pi 0 within the drum chamber being closed to t e admission of air except at its said upper open tubular enda compressed air supply pipe which discharges directly into the drum chamber, said bearing being stationary and the discharge pipe and the compressed air supply pipe being mounted in said bearing; and a movable shield for the bination with a bent discharge pipe which is.

tubular from end to end and which has Within the drum chamber an upstandin tubular portion, the upper tubular end 0 which is open,'adjacen-t and below the discharge end of a blade as the blade comes to the top of the drum, the discharge pipe Within the drum chamber being closed to t e admission of air except at its said upper open tubular end; and a compressed air suppl pipe which discharges into the drum 'cham er, the blades severally havin an apical stream discharging edge for tion of a stream into the open tubular ad acent end of the upstanding portion of the dischargepipe.

In testimony whereof I have hereunto set my hand this 3rd day of May, 1917.

WYLIE GEMMEL WILSON. 

